zephyr/modules/trusted-firmware-m/interface/interface.c

102 lines
2.4 KiB
C

/*
* Copyright (c) 2019,2020 Linaro Limited
* Copyright (c) 2021 Nordic Semiconductor ASA
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr/device.h>
#include <zephyr/init.h>
#include <zephyr/kernel.h>
#include <zephyr/arch/arm/cortex_m/fpu.h>
#include <tfm_ns_interface.h>
/**
* @file @brief Zephyr's TF-M NS interface implementation
*
*/
/* Global mutex to be used by the TF-M NS dispatcher, preventing
* the Non-Secure application from initiating multiple parallel
* TF-M secure calls.
*/
K_MUTEX_DEFINE(tfm_mutex);
int32_t tfm_ns_interface_dispatch(veneer_fn fn,
uint32_t arg0, uint32_t arg1,
uint32_t arg2, uint32_t arg3)
{
bool isr_mode = k_is_in_isr() || k_is_pre_kernel();
int tfm_ns_saved_prio;
int32_t result;
if (!isr_mode) {
/* TF-M request protected by NS lock */
if (k_mutex_lock(&tfm_mutex, K_FOREVER) != 0) {
return (int32_t)PSA_ERROR_GENERIC_ERROR;
}
#if !defined(CONFIG_ARM_NONSECURE_PREEMPTIBLE_SECURE_CALLS)
/* Prevent the thread from being preempted, while executing a
* Secure function. This is required to prevent system crashes
* that could occur, if a thread context switch is triggered in
* the middle of a Secure call. Note that the code below takes
* into account MetaIRQ, which can preempt cooperative threads
* of any priority.
*/
tfm_ns_saved_prio = k_thread_priority_get(k_current_get());
k_thread_priority_set(k_current_get(), K_HIGHEST_THREAD_PRIO);
#else
ARG_UNUSED(tfm_ns_saved_prio);
#endif
}
struct fpu_ctx_full context_buffer;
z_arm_save_fp_context(&context_buffer);
result = fn(arg0, arg1, arg2, arg3);
z_arm_restore_fp_context(&context_buffer);
if (!isr_mode) {
#if !defined(CONFIG_ARM_NONSECURE_PREEMPTIBLE_SECURE_CALLS)
/* Restore thread priority, to allow the thread to be preempted. */
k_thread_priority_set(k_current_get(), tfm_ns_saved_prio);
#endif
k_mutex_unlock(&tfm_mutex);
}
return result;
}
uint32_t tfm_ns_interface_init(void)
{
/*
* The static K_MUTEX_DEFINE handles mutex initialization,
* so this function may be implemented as no-op.
*/
return PSA_SUCCESS;
}
#if defined(TFM_PSA_API)
#include "psa_manifest/sid.h"
#endif /* TFM_PSA_API */
static int ns_interface_init(void)
{
__ASSERT(tfm_ns_interface_init() == PSA_SUCCESS,
"TF-M NS interface init failed");
return 0;
}
/* Initialize the TFM NS interface */
SYS_INIT(ns_interface_init, POST_KERNEL,
CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);